Telescoping collapsible platform support



Aug. 26, 1969 N, Q. CLOVER 3,463,255

TELESCOPING COLLAPSIBLE PLATFORM SUPPORT ATTORNEY Aug. 26, 1969 N. Q.cLovr-:R

TELESCOPING COLLAPSIBLE PLATFORM SUPPORT 2 Sheets-Sheet 2 Filed July 8,1968 A TTURNEY United States Patent O U.S. Cl. 182-17 18 Claims ABSTRACTOF THE DISCLOSURE A supporting frame for a work platform has pairs ofadjusta-ble telescoping tubular legs mounted on opposite ends of a basewith rungs connected between the upper extensible portions of adjacentlegs. Horizontal members extending between opposite legs support theplatform and provide guard rails, while tensioning members maintain thelegs in a stable vertical position. The legs are pivotally mounted tofold down onto the base forV storage and portability.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to a work platform support and particularly to a novel structuretherefor which is adjustable in height to meet varying conditions andwhich may be folded into a compact horizontal position.

Description of the prior art Previous adjustable platform supports haveutilized relatively short outer tubular members which were raised orlowered to a desired height on longer inner vertical legs. Horizontalmembers extending between the outer members on four legs providedstability and support for the platform. Some frames of this type havealso been foldable into a common vertical plane by pivoting the outertubular and horizontal members about the inner legs. These devices,however, have been somewhat cumbersome and complex and are not readilyadaptable for a variety of uses and conditions.

SUMMARY OF THE INVENTION It is therefore the primary object of thepresent invention to provide a simplified sturdy adjustable platformsupport which can be utilized in varied positions and is readilycollapsible into a convenient horizontal form.

These objects and advantages are achieved by a novel arrangement whereina plurality of long outer tubular leg members extend from and aretelescoped over a set of inner lower vertical legs which are pivotallymounted on a base. Horizontal rungs connect adjacent pairs of legs, andother detachable horizontal members between upper portions of the legsat opposite ends support the platform and provide a guard rail. Thepivotal connection of the legs on the base permits folding the entireplatform support into a compact horizontal position. The platform isadjusted to a desired height by inserting pins into holes along thelower legs to engage the upper legs while adjustable turnbuckles andtension cables maintain the legs in a stable vertical position. Theinvention will be more fully understood and other objects and advantageswill become apparent by reference to the accompanying drawings anddetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE l shows the platform support inan upright unextended position;

FIGURE 2 shows in greater detail the pivotal mounting for a leg on thebase;

3,463,265 Patented Aug. 26, 1969 DESCRIPTION OF THE PREFERREDEMBODIMENTS As shown in FIG. l, pairs of rectangular hollow tubular legs10, 12 are mounted at opposite ends of a supporting base structure 14.The base is formed of pairs of longitudinal and transverse horizontalmembers 16, 18 which are also preferably of rectangular metal tubeswelded together. The base is mounted on four wheels 20 which turn withinvertical members 22 which rotatably engage tubular extensions 23 securedto the base. The length of vertical members 22 may be changed if desiredto permit adjustment of the height or orientation of the platformsupport structure in Various applications. The wheels may also be lockedin a xed horizontal position by locking devices 24 to preventundesirable movement.

The legs are pivotally secured to the base by means of a bolt or pin 26mounted in a channel or bracket 2S, which may be welded to the base, asshown in more detail in FIG. 2. The legs include an inner lower member30 pivotally mounted in bracket 28 and an outer upper 4member 32telescoping over and extensible from the inner member. FIG. 1 shows theupper members in a fully extended position. A plurality of rungs 34 areconnected between adjacent pairs of legs to form a step ladder at eachend of the frame. The rungs may be secured on each leg by adjustableclamps 36 or may be permanently welded thereto.

The height of the legs is adjusted by raising the upper members of eachpair of legs on each end to a desired level and then inserting alocating bolt or pin 38 into a hole 40 in lower member 30 at the closestpoint. A series of such holes are spaced at predetermined intervals ofseveral inches along the length of each lower leg member, with all holesbeing aligned and spaced equally on each leg to maintain a levelarrangement. Removable pins are provided for each leg, with the pinsengaging inverted U-shaped slots 42 at the lower end of each upper legmember to support the upper members in the desired position. The legsare lowered by removing the pins and sliding the upper members down overthe lower members. In the completely telescoped position, upper legmember 32 lits over lower member 30V within bracket 28, with slot 42engaging pin 26.

A work platform 44, typically of 1/z-inch plywood, is preferably boltedon two horizontal members 46 extending between and detachably supportedby rungs on legs at opposite ends of the frame. The platform and supportmembers may be placed between rungs at any desired level. Flangesextending from members 46 abut the'rungs to prevent movement of theplatform. A second4 pair-of detachable horizontal members 4S extendacross the top of the upper legs between opposite ends along each sideof the structure and provide a guard or safety rail at a predeterminedlevel above the platform. The vertical ends 50 of the guard rail membersmay fit within the hollow tubular openings at the tops of the upper legmembers or may be of larger tubular cross-section to t over the top ofthe legs. The height of the vertical ends S() may be varied to raise orlower the guard rail for particular safety requirements.

Since the legs pivot on the base, in order to maintain the legs in astable rigid vertical position, adjustable tension cables or wires 52,54 are connected between an upper portion of an upper leg member such aseyelet 56 to a lower portion, such as eyelet 58, of the upper leg memberat the opposite end of the frame on the same side. The tension cablesfor adjacent legs on the same end are connected to opposite portions, asshown in FIG. l. Thus, cable S2 is connected between eyelet 56 on theupper portion of upper leg member 32 of one leg of adjacent pairs oflegs and the eyelet 58 on the lower portion of the upper member of theleg of opposite end pair 12 on the same side of the structure, whilecable 54 connects from eyelet 60 on the upper portion of the other legof adjacent pair 12 to eyelet 62 on the lower portion of the other upperleg member of adjacent pair 10. The cables, which are typically of aboutinch in diameter, are connected by means of hooks 64 to respectiveeyelets, and turnbuckles 65 permit adjustment of the tension to maintainthe legs in a rigid vertical position under varying changes in height ororientation. In the fully extended position, such as shown in FIG. 3, asecond pair of tension cables 66, 68 are provided to further assurestability. In this case cable 66 is connected from the same eyelet 58 onthe lower portion of the upper leg member 32 of adjacent pair 12 to aneyelet 70 pivotally mounted on the lower portion of the lower leg member30 of the leg of pair 10 on the same side, while cable 68 is connectedfrom eyelet 62 of upper member 32 of the other leg of pair 10 to anotherpivotable eyelet 72 on the lower leg portion of the other leg of pair12. In this manner the entire frame in the extended position is held ina firm, stable position.

In order to maintain stability and for safe operation the height of theplatform should be no greater than about four times the width of thebase. Thus, for a base of 2.5 feet the platform should be no higher than10 feet. For greater heights, the width of the base should be increasedproportionately. The various hollow tubular metal mem bers are typicallyof about 11/2-inch square cross-sections with the lower leg membersbeing about 11A-inch squares, and all members of the frame arepreferably of high strength structural steel.

In the extended position, the rungs 34 between adjacent pairs of legs oneach end are raised considerably above the level of the base. Thereforea removable extension ladder 74 is provided which may be hooked over alower rung on either end to extend between the legs down to the base ata desired level, A chain type ladder may also be employed for thispurpose.

In many circumstances the terrain or ground level on which a platformsupport is to be used is not horizontal and may slope at relativelysteep angles. The usual fixed support structure and platform wouldmerely be set parallel to the ground with the workman having to stand onthe angled platform as best he could or else the support often could notbe used at all. The present invention obviates this diiculty due to thepivotal mounting and telescoping arrangement of the legs. As shown inFIG. 4, the base 14 may remain parallel to a sloping ground level, whileone pair of legs 12 at the lower end may be raised to a higher positionthan the other pair 10. The tensioning cables are first loosened, legs12 raised and pins 38 inserted into holes 40 at the required higherlevel on lower leg members 30 of pair 12, with the cables then beingretightened. Both pairs of legs thus pivot into a vertical position andrthe platform is supported in a horizontal position while the baseorientation remains parallel to the sloping surface.

As shown in FIG. 5, the entire platform support is collapsible tofacilitate storage and portability, with adjacent pairs of pivotallymounted legs 10, 12 being foldable onto base 14 from opposite ends. Onepair of legs 10 at one end is preferably spaced closer together ontransverse base member 18 so that it folds down within the space betweenparallel longitudinal base members 16 and within the space between theopposite pair of legs 12. A special flange 76, shown in FIG. 1, extendsfrom the inner side of the opposite transverse base member 18 to supportthe free ends of legs 10 in the folded position while legs 12 rest onbase members 16 and legs 10. .Tn the process of collapsing thestructure, the legs are lowered into the unextended telescoped position,the platform 44 and supports 46 are removed along with guard rails 48,the tension cables are loosened and hooks 64 removed and then the legsare folded onto the base. The extension ladder may 4be hooked onto thetop rung between legs 10 and folded down therewith. In anothervariation, both pairs of legs may retain the same spacing with one pairof legs being mounted so that the pivoted end is raised on base member18 to permit it to be folded down from a higher level onto the otherpair in a horizontal position without interference. In this case somecompensating change would be necessary on the raised legs such aslowering the holes or rungs to maintain the platform and guard raillevel with respect to both pairs of legs at opposite ends of thestructure.

The present invention thus provides an improved telescoping collapsibleplatform support which is safe and stable in use and readily adaptableto varying conditions. While only a single embodiment has beenillustrated, it is to be understood that many other variations may bemade in the design and conguration Without departing from the scope ofthe invention as set forth in the appended claims.

What is claimed is:

1. A platform support comprising a base having pairs of longitudinal andtransverse horizontal members, pairs of tubular legs mounted at oppositeends of said base, each leg including an inner lower member pivotallysecured to said base and an outer upper member telescoping over andextensible from said lower member, a plurality of rungs mounted on saidupper members between adjacent legs at each end, detachable supportmeans extending horizontally between said upper leg members at oppositeends, and means for adjustably securing said legs in an upwardlyextending position at a predetermined height, said pairs of legs beingfoldable onto said base from said opposite ends.

2. The device of claim 1 wherein said means for adjustably securing saidlegs at a predetermined height includes a plurality of holes spacedalong the length of said lower members, a removable pin for each legengageable with a hole therein, and means on said upper members adaptedto engage said pins to maintain said legs at said height.

3. The device of claim 2 wherein said detachable support means includesa platform extending horizontally between rungs on said legs at oppositeends and a pair of detachable horizontal members extending along eachside connected between said opposite legs and being mounted above saidplatform to provide a guard rail.

4. The device of claim 2 wherein said adjustable securing means includesa pair of adjustable tension cables each connected between an upperportion of one leg and a lower portion of the other leg at the oppositeend on the same side, adjacent legs having said cables connected toopposite portions.

5. The device of claim 2 wherein said means on said upper members toengage said pins includes an inverted U-shaped slot at the lower end.

6. The device of claim 2 wherein said legs are of hollow rectangularmetal tubing.

7. The device of claim 2 wherein said base is mounted on wheels andincludes means for locking said wheels in a iixed horizontal position.

8. The device of claim 2 wherein said legs are secured in a verticalposition.

9. The device of claim 2 wherein said platform support in an extendedposition includes a detachable ladder mounted on said upper members ofsaid adjacent legs and extending down toward said base.

10. The device of claim 2 including means adjustably securing said rungsto said upper members.

11. The device of claim 2 wherein one pair of adjacent legs at one endis spaced closer together than that at the other end so that said onepair is folded within the other onto said base.

12. The device of claim 3 wherein said platform is mounted on a secondpair of detachable horizontal members extending between said rungs onlegs at opposite ends.

13. The device of claim 3 wherein the ends of said guard rails engageopenings in the ends of said upper leg members.

14. The device of claim 3 wherein the ends of said guard rails haveopenings engaging the ends of said upper leg members.

15. The device of claim 3 wherein each pair of legs is separatelyadjustable in height to maintain said platform horizontal with said basebeing angularly oriented on differently sloping ground levels.

16. The device of claim 4 wherein said platform support in an extendedposition includes a first pair of said adjustable tension cables, and asecond pair of tension cables each connected between lower portions ofthe upper leg members and a lower portion of a lower member of theopposite leg.

17. The device of claim 5 including a pivot member References CitedUNITED STATES PATENTS 2,354,906 8/1944 Bailey 182--152 2,593,386 4/1952Dirks l 182--152 3,028,928 4/1962 Juculano` 182-178 3,186,512 6/1965Johnson 182-152 REINALDO P. MACHADO, Primary Examiner U.S. Cl. X.R.

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